The present invention generally relates to air bags and more particularly a method of folding an air bag used for side impact collision protection.
The way an air bag is folded, especially a side impact air bag (used to protect an occupant during a side impact or collision), provides an opportunity for controlling the air bag inflation dynamics including the direction and motion of the inflating air bag. As an air bag inflates it unfolds and various parts of the air bag are propelled outwardly, from its compact or folded condition. The air bag, however, does not immediately completely inflate. Typically, as an air bag inflates various still-folded parts are unfurled as a unit or mass. The mass of these partially unfolded parts, when accelerated during inflation by the inflation gas, may impact an occupant in a forceful manner. The present invention is directed to a method of folding an air bag such that when the air bag is inflated and unfolds, the air bag will avoid directly impacting the occupant especially the out-of-position occupant such as one seated too close to the side door of the vehicle. Most people, in this art, have defined the normally-seated occupant as one seated in the center of the seat, with the seat at its mid-range of fore-aft travel with the seat back at its designed angle. The out-of-position occupant is one that is seated in a position that deviates from the normally-seated position.
Most of the critical out-of-position injuries from side air bag inflation occur at an early stage of bag unfolding, that is, right after the air bag fully emerges from the seat. The proposed fold has shown significant improvement in out-of-position testing. The fold, of the present invention, encourages the partially unfolded parts of the air bag to swing away from the occupant, such that the resultant force vector of the inflating air bag is directed upward, and forward and laterally into adjacent vehicle structure such as a door or B-pillar. This desired motion of the unfolding of the leading edges of the air bag material (typically of a head chamber of the air bag) prevents a potential direct impact between an occupant body part by the relatively heavy and fast moving mass of air bag material thus avoiding injury to the occupant. As the cushion or air bag interacts with the lower torso of the occupant, the head portion of the cushion begins to fill reducing the loading effect that could be transferred to the occupant.
Accordingly the invention comprises an air bag and method of folding an air bag to protect an occupant during a side impact collision, the air bag being part of an air bag module fitted within an outboard portion of a vehicle seat, the method including the step of folding the air bag into a compact configuration such that when inflation gas is communicated into the air bag a resultant momentum vector, of the unfolding air bag sections, is directed forward of the seat and laterally away from a location of a seated occupant.
It is an object of the present invention to provide an improved method of folding an air bag.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.